Using a REPL with a Microcontroller #Python #MicroPython #CircuitPython @hackaday
Elliot Williams writes on Hackaday about using a shell, a read-eval-print loop (REPL) in which you can interactively try out your code just about as fast as you can type it.
(A REPL) great for interactive or exploratory programming, and it’s great for newbies who can test and learn things step by step. A good REPL lets you test out your ideas line by line, essentially running a little test of your code every time you hit enter.
The obvious tradeoff for ease of development is speed. Compiled languages are almost always faster, and this is especially relevant in the constrained world of microcontrollers. Or maybe it used to be. I learned to program in an interpreted language — BASIC — on computers that were not much more powerful than a $5 microcontroller these days, and there’s a BASIC for most every micro out there. I write in Forth, which is faster and less resource intensive than BASIC, and has a very comprehensive REPL, but is admittedly an acquired taste. MicroPython has been ported over to a number of micros, and is probably a lot more familiar.
But still, developing MicroPython for your microcontroller isn’t developing on your microcontroller, and if you follow any of the guides out there, you’ll end up editing a file on your computer, uploading it to the microcontroller, and running it from within the REPL. This creates a flow that’s just about as awkward as the write-compile-flash cycle of C.
What’s missing? A good editor (or IDE?) running on the microcontroller that would let you do both your exploratory coding and record its history into a more permanent form.
Ed. note: CircuitPython and the Mu Editor provide the described environment
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